Electric-arc lamp



(No Model.)

BLBGTRIC ARG LAMP.

Rw A W s R 8 E 1lv5 4JL m Onw. n O N E 9.. k M L w wo I O a e Mm m A ,eKM a. m d S I E m M m k l E m. w w g H N E m E j W m m D.. T m N L M .frA E WM d 1. E E No m ,e m w m M E; WM Pfw KM m j MY FB UNITED STATESPATENT OFFICE.

LEWIS WALCOTT SPENCER, OF HOOSIOK FALLS, AND FREDERICK PO\VERS JAQUITH,OF HOOSICK, NEW YORK.

ELECTRIC-ARC LAMP.

SPECIFICATION forming part of Letters Patent No. 388,594, dated August28, 1888.

Application tiled October 12, 1885. Serial No, 179,6f8. (No model.)

To all whom it may concern.-

Be it known that we, LEWIS VALeoTT SPENCER and FREDERICK IowEEs JAQUITH,respectively of Hoosick Falls and Hoosick,in

the county of Rensselaer and State of New York, have invented certainImprovements in Electric-Arc Lamps, of which the following description,in connection with the accompanying sheet of drawings,constitutesaspecication. y

This invention relates to special mechanism for automatically regulatingthe feed of the movable toward the stationary carbon of an arc lamp, andto provisions connected therewith for effecting the primary adjustmentof the movable carbon with reference to the fixed carbon.

I have shown in the drawings only the movable or upper carbon inconnection with the devices for controlling its adjustment and feed,including the main magnets and the shuntmagnets with an interposedcommutator.

The drawings fully illustrate the invention, wherein- Figures l and 2show, respectively, a side and a front elevation of my apparatus. Fig. 3exhibits a plan of the same after removal of the upper supporting-plateof the frame structure. Fig. 4t is a partial longitudinal section of theupper portion of the guide-tube in which the carbon-h olderstem works.Fig. 5 is a transverse section through top of guide-tube taken on line 12 ot Fig. 4. Fig. 6 is a view of the under side of main magnets,showing` shape of the armature. Fig. 7 shows details of constructionofthe nutand its connections.

In carrying out my invention, for convenience I mount my apparatusbetween two plates,A and B. Apair of electric coils,C C,is placed in themain circuit, as shown. From the bar spanning the tops of the magnets apendulum-rod, D, is hung, so as to swing on the hinge-joint E. To thebottom of rod D the armature H is attached. This armature which carriesthe nut I. This nut is seen in side elevation in Fig. l as pivotedbetween cheeks aa, and is of elbow form, its upper part being fitted toengage with the thread on the rod J. The cylinder is provided with anannular ratchet, K, with which pawl L works. This pawl is pivoted on anoscillating plate, M, which isjournaled on cylinder b, and has itsreciprocating motion imparted to it from the pendulous movement ofswinging armature d, connected with the shnntcoils O O. Thecarbon-holder A is attached to the lower end of stem J, and has ascrew-clamp, C', for securing the carbon in place.

The stem .I is provided with a ratchet screwthread, as shown, and nutIis correspondingly threaded to engage therewith. Nut I is held inengagement with the screw by a spring in its hinge-joint, or by otherappropriate me- 7o ehanical means. This construction of thread possessesspecial advantages. Vhen it becomes desirable to insert a new carbon,the carbon-holder may be grasped by the hand and forced up to its properaltitude, the ratchet form of the thread permitting the screw to beslipped along or over the yielding nut I. The ratchet form of threadalso facilitates the removal from the various bearings through which itpasses of any deposited soot or products of combustion of the carbon,which often interfere with the proper action of delicate regulatingmechanism. The nut also acting on only one side of the screw serves as ascraper to clean from the thread any accumulations which may haveadhered thereto.

The stem .I is adjusted to work vertically in a tubular chamber, D,erected over the axis of the carbon-holder upon the plate A. It is madeof a length to snit the length of carbon to be used in the lamp. Fig. iillustrates its details of internal construction and shows the upperpart of the stem of the carbonholder in working position. This tubeconsists of two longitudinal semi-tubes provided with wings or ears SS', whereby they can be united. Between the semi-sections twolongitudinal slides, E E, are inserted, and the combination so formed isheld together by screws or bolts through the cars S S".

To the top of stem J is attached a ball or cross-head carrying lateralguides F F', which IOO co-operate with slides E E. These provisionspcrmit the stem J freely but accurately to slide up and down within tubeD', and at the same time prevent the screw from turning. They also serveto maintain the burning-point of the carbon in apposition with the pointof the under carbon.

The commutator consists of a small cylinder, Z, mounted in frame XV. Inthe upper surface of the cylinder is inserted a strip of non-conductingmaterial, n, and directly over this the brush X works. Brush Xisinsulated, but the current is transmitted by the usual means from thesame to the shunt-coils O O. Cylinder Z has a crank-pin, n', at one end,whereby connection by the pitman is made with the pendulum N of theshunt-coils. By these means the oscillation of the pendulum N, by reasonof the attraction and repulsion of armature (l, causes cylinder Z torotate on its bearings, so that the insulating-piece a is rotated out ofcontact with brush X, and the same is permitted to come into contactwith the material of the cylinder Z, thus establishing the circuitdirectly from the main to the shunt coils.

The shuntcoils O O are similar in construction to the main coils, andare provided with an armature of wedge shape, d, attached tothe end of apendulum, l hung from the crossbar F". A longitudinally-adjustableconnecting-rod is pivoted at one end to the crank-pin e and at the otherend to the armature d by a joint connection, g, as seen in Fig. 3. Bymeans of a right-and-left hand screw and nut, N, the length of thisconnecting rod or pitman maybe adjusted. By these appliances theattraction and repulsion of armature d impart reci p rocating motion topawl L on arm llLwith which the pitman just described is connected. Bythe rcciprocation of pawl D,working in engagement with ratchet K, anintermittent progressive rotary movement is imparted to nut I, withwhich the ratchet K is connected, and thereby the carbon-holder isintermittently lowered.

From the axis of pendulum N a short arm, Q, is erected, which isconnected by means of a retractile spring` with a fixed bracket, T,connected with the frame of the lamp. The tension of spring S isadjusted by screw R. The repellent movement of armature d is limited byset-screw S. The normal course of the current is from the dynamo orother source of supply to the .main magnets C G, thence through thestructure of the upper carbon holder to the upper carbon, and from thatthrough the lower carbon to the source.

The lamp is equipped and operated as follows: Any suitable or convenientdevice may be used to hold the lower carbon or electrode, which shouldbe isolated by insulation from the upper-carbon holder. Thecarbon-holder should be shoved up high enough to insert the carbon inthe clamp-socket A', where it is secured by screw C'. It may then belowered to its approximate adjustment, or until the points ceases of thetwo carbons are in contact, by throwing nut I out of engagement with theratchetthread of the stem J, which is easily done by depressingthumb-piece e. Contact between the carbons being established, thecurrent is turned on, whereby the magnet-cores are magnetized andarmature H is drawn into contact therewith, whereby the position seen inFig. 2 is established. rIhis movement. acting through bracket F andstirrup G, which is pivoted to an appurtenance of the carbonholder,produces an elevation of the carbonholder, and consequently a separationof the carbon points whereby the arc is established. This status ismaintained until the interval between the carbon points, by reason ofthe consumption of the ends of the carbons, has become so great and theresistance to the passage of the current by this path so high that itseeks a passage through the commutator, the principle of constructionbeing such that when the resistance offered by the non-conductor n ofthe commutator is less than that offered by the interval between thepoints ofthe carbons the current will follow the path of leastresistance and pass by the commutator to and through the shunt-coils. Asa result of this diversion of the current, t-he shunt-coils becomemagnets, and, by attracting armature d through the before-describedconnectingpitmen, cause a movement of ratchet K in the direction torotate the nut I, so as to let the ratchet screwstem and attached carbondown, and at the same time rotating the commutating-cylinder, so as tothrow the resisting-piece n into the circuit, whereby the same, inobedience to the law of following the line of least resistance, seeksits normal path through the carbons, as in the first instance. Thisopera tion is repeated as often as the preponderance of resistance istransferred from the route through commutator to the interval of theare.

If found necessary or desirable, sectional nuts similar to nut I may beapplied at other points about the threaded stem.

Hence we claim- 1. In an electric-arc lamp employing a movable and astationary carbon, a holder for the movable carbon provided with ascrewthreaded stem, a rotating sectional nut with which such stemengages, said nut being in combination with a concentric ratchet, and apawl actuated by the movement of the armature of a shunt-magnet-,whenconstructed and arranged to operate substantially in the manner setforth.

2. In an electric-arc lamp, a vertically-movable non rotating carbonholder having a screw-threaded stem, a hollow cylindrical nutcarrierprovided with a concentric ratchet, anda sectional nut adapted to engagewith the thread of the screw-stem of the carbonholder which passesthrough the center of said carrier, and about which said carrierrevolves, a concentric collar for supporting said carrier, which collaris connected with or attached to the armature of the main magnets,substan- IOO IIO

tially as shown, whereby a rising-and-falling movement may be impartedthereto, in combinatien with a reciprocating or oscillating arm carryinga pawl which actuates said ratchet by means of the vibration of thearmature of a shunt-magnet with which said arm is connected,substantially as shown, and for the purposes set forth.

3. The combination of the carbon-holder havingstem lTand guide-lugs FF,with the tuhular gnideway D', having the parallel ribs E E, whichco-operate with lugs F F, substantially in the manner described, and forthe purposes set forth.

4. In a regulator for are lamps, the combination of the magnets() C,shunt-coilsO O,swing ing pendulum-rods N and D, armatures H and d,stirrnp G, collar H, cylinder b, and nut I, cylinder Z, insulatingpiecen, and brush X, substantially as set forth.

5. In a regulator for are lamps, the combiscribed our names, at Hoosick,this 29th day 3 5 of September, A. D. 1885.

LEWIS WALCOT'I SPENCER. FREDERICK POWERS JAQUI'IH.

In presence of FRANKLIN SCOTT, C. H. HOUGHTON.

